Do classical concerts need complex lighting plots? Unless a composer specifically asks for them, I would have thought not, though the Britten Sinfonia clearly think differently. Their latest Barbican concert – directed by leader Jacqueline Shave and structured around themes of night, sleep and dreams – was hampered in places by unnecessary visuals.

The players arrived on a platform bathed in a creepy, radium-green glow before playing the first two pieces – the Adagietto from Mahler's Fifth Symphony and Henze's L'Heure Bleue – in a chiaroscuro generated by the lights of their music stands. In pitch darkness, meanwhile, some audience members read programme notes from the light of their mobile screens. It all got in the way of exemplary musicianship: Henze's depiction of twilight, sexual yet dangerous, was particularly glorious.

The evening's centrepieces, however, were vocal, so the lights reverted to normal. First came the premieres of three of Detlev Glanert's orchestrations of Schubert songs, reworkings that weave subtle changes into the originals. For instance, the figurations that accompany Das Lied im Grünen, which in the piano version suggest the rambler's footsteps, hint at the rustling natural world around him when transferred to strings. The orchestrations sound uncannily like genuine Schubert, except for Waldesnacht, which has a sombre quality reminiscent of Weber. Ian Bostridge, on fine form, sang them with great intellectual insight and intensity.

Britten's Nocturne – his profound meditation on the homoeroticism and political anger that informed his creativity – brought the evening to its close. Bostridge showed impeccable understanding of its subtle fluctuations between erotic reverie and nightmare. The instrumental solos that track the dreamer's progress were exquisitely done, while the string lullaby that binds the work together took us into shifting emotional territory with each repetition. Exceptional.